Apparatus and method for detecting and measuring radiant energy for locating subterranean petroleum deposits



Feb. 15, 1949.

2,461,803 G AND ,1 Y'fi? AMPLIFIER RECORDER ARMSTRONG m ss 53 r 3 ,m

01 lglnal Flled March 6 1945 SUBTERRANEAR PETROLEUM DEPOSITS APPARATUS AND METHOD FOR DE MEASURING RADIANT ENERGY FOR LO m 0 R M R. A R m m w Patented Feb. 15, 1949 UNITED STATES PATENT OFFICE APPARATUS AND METHOD FOR DETECTING AND MEASURING RADIANTENERGY FOR LOCATING SUBTERRANEAN PETROLEUM DEPOSITS Walter Armstrong, Washington, D. 0.

Original application March 6, 1945, Serial No.

581,280. Divided and this application September 20, 1945, Serial No. 617,589

6 Claims. 1

and measuring radiant energy for locating subterranean petroleum deposits.

I have found that the penetrating radiant energy emanating from subterranean petroleum deposits which reaches the earths surface is proportional to the nature and amount of the subterranean petroleum deposit and the intervening earth strata. Because of the varied nature and intensities of this energy encountered in the various locations to be explored, various types of apparatus have been designed.

Through my construction and trial of apparatus I have learned that a negative electrostatic charge, when placed on the inner walls of a suitably shielded ionization chamber constructed of inactive material, has the peculiar property of uniting with electrons produced on the inner walls of the ionization chamber. I have also learned that when additional electrons, resulting from the penetration of external radiation to the inner walls of the shielded ionization chamber, are contacting the initially negatively electrostatically charged inner walls, these additional electrical charges on the inner walls will produce corresponding charges of the opposite polarity, or positive charges, on the ionization chamber electrode.

These principles in the field of molecular and electron physics have been fully disclosed in my co-pending application Serial No. 547,940 filed August 3, 1944, entitled "Method of detecting and measuringradiant energy for locating subterranean petroleum deposits. Myinvention provides a method and apparatus for utilization of the radiant energy emanating from subterranean countered in geophysical explorations.

petroleum deposits, for field use in petroleum.

prospecting.

In my apparatus 1 use an ionization chamber in an inclosing shield which shields the ionization.

chamber from earthly ionizing radiation incident upon the shield in geophysical explorations, such as alpha, beta, and gamma, as well as other ionizing radiation associated with the penetrating radiant energy emanating from subterranean petroleum deposits, all of which radiation accelerates the discharge of an. ionization chamber charge. The inclosing shield, except for a portion of the shield between the ionization chamber and the earths surface, also shields the ionization chamber against the radiant energy emahating from subterranean petroleum deposits en- The apparatus also shows structure and means for the electronic determination of the ionization chamber charge during the operation of the apparatus with the apparatus mounted on trunnions for selectively adjusting the position of the apparatus in relation to the earths surface.

The penetrating radiant energy which emanates from subterranean petroleum deposits which I detect and measure by the apparatus of my invention, has penetrating properties far greater than the above-described ionizing radiation which accelerates the discharge of an ionization chamber charge, and because of the great penetrating properties of the radiant energy reaching the earths surface from subterranean deposits of petroleum, the petroleum deposit emanations penetrate through the inclosing shield provided in my apparatus for shielding the ionization chamber from the ionizing radiation, encountered in geophysical explorations, that accelerates the discharge of an ionization chamber charge. The petroleum deposit emanations when penetrating the shielding above a recess in the inclosing shield and on to the inner walls of the ionization chamber on which there has been placed a negative electrostatic charge, will cause additional electrons, or negative charges, to adhere to the already initially negatively electrostatically charged inner walls. These added charges to the inner walls will cause a retardation in the dissipation or decay of the ionization chamber charge. Thus I have shown that the ionization chamber in my apparatus is used for the purpose of affording a shielded negatively electrostatically charged surface for collecting electrons, or negative charges, thereon, which additional charges on the inner walls of the ionization chamber are caused by the penetration to the ionization chamber of the penetrating radiant energy reaching the earths surface from subterranean petroleum deposits.

The apparatus of this invention is mounted on trunnions for facilitating the detection and measurement of the radiant energy emanating from subterranean petroleum deposits by permitting the detection and measurement from any desired angle in relation to the earths surface.

The principal object of this invention is to provide apparatus and method employing adjustableangular or tilting shielding for the detection and measurement of relative values of the petroleum deposit emanations encountered at selectively adjusted angles in relation to the earths surface.

Another object of my invention is to provide apparatus the operation of which will furnish angular determinations of the radiant energy emanating from subterranean petroleum deposits encountered at selected locations on the earth's surface for use in petroleum explorations.

Those and other objects of my invention will be evident from the following disclosures and the appended claims.

The method of my invention will be more fully understood from the specifications hereinafter following by reference to the accompanying drawings in which:

Figure 1 is a vertical sectional view of my exploratory apparatus embodying the principles of my invention and arranged for angular adjustment in a vertical plane for facilitating the focusing of the ionization chamber with respect to the area being explored; Figure 2 is an end view of the apparatus illustrated in Fig. 1 and showing in dotted lines the angular positions to which the exploratory apparatus may be selectively adjusted in carrying out my invention.

The ionization chamber may follow the general construction of any type of electroscope, electrometer, orother current or voltage measuring device.

When single shielding is used pure inactive lead may be employed; however, the shield may be of any particular single, multiple, or combination, of metallic, non-metallic, liquid, or gaseous types of construction having physical properties of shielding or causing the disintegration'of radiant energy or causing secondary radiation.

When additional electrons, or negative charges, are added to the initially negatively electrostatically chargedinner surface of the suitably shielded ionization chamber, resulting from the penetration to the ionization chamber of the penetrating radiant energy which emanates from subterranean petroleum deposits, those added charges produce corresponding positive charges on the ionization chamber electrode charge which causes a retardation in the dissipation of the electrode charge. This retardation is observed from the recordings of the amplified ionization chamber electrode charge during the time period the apparatus is in operation.

The apparatus may take the form of an ionization chamber, the charged electrode, electrodes, or insulated walls of which are connected to a shielded electronic amplification unit, through the intermediary of an extremely low loss condenser unit, or connected directly to an electronic amplifier. However, such an amplification unit must be so constructed that its operation will cause an extremely low loss of the ionization chamber charge. Other refinements, such as shielding of electrical components from all possibility of inducing primary or secondary charges, and the elimination of residual or bound charges, are essential to my apparatus for electronic amplification of the ionization chamber electrode charge.

The figures portray an inclosing shield mounted on trunnions in which there is an ionization chamber containing an insulated electrode. According to the accepted theory, when the electrode is given a positive electrostatic charge, a corresponding charge of the opposite polarity, or negative, is produced on the surface of the inner walls of the ionization chamber.

The apparatus of this invention provides adjustable angular shielding so that the desired angle of exploration to the petroleum deposit may be great or less according to the needs of the exploration.

Figure 1 is a schematic illustration of the apparatus of my invention provided .with adjustable angular or tilting shielding mounted on trunnions. Trunnions on opposite sides of the inclosing shield l6 extend through the framework support 31 to enable the apparatus to be tilted in its operation to any desired angle with relation to the earths surface.

The inclosing shield l6 surrounds the ionization chamber 4 and electrode 5' therein. The electrode 5' is a rod of brass or other suitable material extending axially into the ionization chamber 4 and is held in place and insulated from the walls of the ionization chamber 4 by insulation 6. The electrode 5' is insulated from the ionization chamber 4 and both the insulator 6 and the electrode 5' are extended to amplification unit 22 within the inclosing shield l6, through the intermediary of an extremely low loss condenser unit, or connected directly to an electronic amplifier within the unit 22 inclosed in the shielded compartment 23 within the inclosing shield I 6'. Any suitable power source such as 22a may be inclosed within compartment 23. Shield 24 is a suitable metallic shield, preferably pure inactive lead which shields the ionization chamber 4 from any primary or secondary charges which might be caused by the amplification unit 22. The inclosing shield l6 also shields amplification unit. 22 against earthly radiant energy.

Passing through an opening 25 in the inclosing shield l6 are insulated wires 26 from the electronic amplification unit 22 to a second electronic amplifier unit 21 which contains apparatus for additional stages of amplification and a current and voltage measuring and indicating device so that the relative values of the electrode charge may be observed or recorded at all times when the apparatus is in operation. The second amplifier unit 2'l-is outside the inclosing shield IS in order to permit the inclosing shield It to shield from amplification unit 22 any induced primary or secondary charges that might be caused through the higher stages of electronic amplification employed in amplifier unit 21.

Insulated wires 28 connect amplifier unit 21 to a conventional recording device 29 which provides recordings of the amplified positive charge on the electrode 5' at all times during the operation of the apparatus.

The inclosing shield l6 rests on a stand or table a on or above the Surface of the. earth although it may be placed in an excavation beneath the surface of the earth. The ionization 01' metal and come within the scope and sphere of my invention.

The inclosing shield l8 diagrammatically represented is'constructed ot-pure inactive lead of the single metal type. in other words solid lead. The inclosing shield l6 may be extended downward as represented at ll' toward theearth. In shield i6 is an axial recess l8 extending upward toward the ionization chamber 4 to the bottom portion l9' of the inclosing shield 16'. The inclosing shield I8, including bottom portion I9 and top portion 20, has shielding capacity to shield the ionization chamber 4 and electronic amplification unit 22 from earthly ionizing radiation such as alpha, beta, gamma and other unwanted ionizing radiation found associated with the penetrating radiant energy emanating from petroleum deposits, all of which radiation accelerates the dissipation or decay of an ionization chamber charge, while the inclosing shield l6, except portions l8 and 20, also has shielding capacity suflicient to shield the ionization chamber 4 and electronic amplification unit 22 against the penetrating radiant energy emanating from subterranean petroleum deposits. I normally use a recess of two inches in diameter which has permitted suflicient petroleum-deposit emanationsto penetrate portion IQ of the inclosing shield l6 and on to the ionization chamber 4 for eflicient operation of the apparatus. The inclosing shield may be constructed and designed to adequately separate the twoforms of radiant energy of varied intensities encountered in geophysical explorations.

Before engaging in field explorations a standard for use in making determinations from measurements obtained in the field under exploration, or normal rate of .dissipation or decay of a positive electrostatic charge on the ionization chamber electrode 5 when shielded against earthly radiant energy, is determined.

Figure 2 is a side view of the apparatus of my invention shown in Fig. 1. The trunnion 30 extending through the framework support 3| may be locked at any desired angle by set screw 32. The trunnion is aligned axially with indicator 33, the ionization chamber 4 and the recess 18' in the inclosing shield l6. Afiixed to the side of the inclosing shield l6 and inalignment with the center of the trunnion 30 is a protractor 34 calibrated from to 90 degrees each side of indicator 3 when the apparatus is in a vertical position.

In field operation the shielded ionization chamber electrode is given a positive electrostatic charge by means of manually contacting a positively electrostatically charged wire 8 to the electrode 5'. The positive electrostatic charge is placed on the wire 8 by contacting wire 8 to a charging unit outside of the apparatus and the wire 8 is disconnected from the charging unit after the electrode has been given the desired charge. To place a positive electrostatic charge on the ionization chamber electrode 8', portion 20' or the inclosing shieldv Wis removed and after the desired number of electrostatic units charge has been given the electrode 5' to permit operation or the apparatus, the wire 8 is turned and made to contact the front or rear of the ionization chamber 4 and portion 20' of the inclosing shield i8 is put back in place. This positive electrostatic'charge on the electrode 5 will produce a corresponding negative charge on the surface of the inner walls of the ionization chamber 4.

In field operation of my apparatus employing the adjustable angular or tilting shielding, the included projected area from which emanations from subterranean petroleum deposits may pass through the recess l8 and be detected and measured may be changed as desired by tilting the apparatus. This apparatus and method reduces costs of petroleum explorations in that a large area may be prospected from one location on the earth's surface. The dotted lines shown in Fig. 2 are representative angular positions to which the apparatus may be selectively adjusted in carrying out my invention.

In field operations at selected locations in the territory to be explored, the shielded ionization chamber with a negative charge on the surface of its inner walls is subjected to the radiant energy which emanates from subterranean petroleum deposits and petroleum deposit emanations encountered will pass through the recess I8 and penetrate portion l9 and on to the ionization chamber 4 and cause negative charges, or electrons, to be added to the negatively charged surface of the inner walls of the ionization chamber 4. Those added charges will produce corresponding positive charges on the ionization chamber electrode 5' which causes a retardation in the rate of dissipation or decay of the electrode charge over and above its normal rate of dissipation or decay. The electrode charge during the operation of the apparatus is amplified by amplification unit 22, within compartment 23 shielded from the ionization chamber 4 by shield 24, and further amplified by amplifying and indicating unit 21 which is connected to recording unit 29 which provides recordings of the ionization chamber electrode charge during the time period of operation of the apparatus.

A recording is made of the amplified value of the electrode charge obtained during the time period of operation of the apparatus and that value is compared with the value of the electrode charge recorded for a like time period when obtaining the normal rate of dissipation at point of exploration. Any retardation noted evidences the presence, and the extent or amount of such retardation evidences the relative amount of the radiant energy encountered from the projected area of the subterranean petroleum deposit.

The apparatus is placed progressively at selected locations on the surface of the earth in the territory to be explored and the negatively electrostatically charged inner walls of the ionization chamber 4 are subjected to the radiant energy emanating from subterranean petroleum deposits. Recordings are made of the locations where angular observations have been taken and of the detections and measurements of the petroleum deposit emanations encountered, and by correlating such observations in the territory under exploration the bounds of the petroleum deposit emanations encountered may be charted. If the petroleum deposit emanations encountered are so intense that the ionization chamber charge of the inclosing shield i6 will not dissipate within a reasonable time, apparatus employing other shielding may be used.

In the foregoing description and explanation of my invention, I have utilized "certain specific formsof construction to more clearly explain the principles upon which it operates, and to so fully describe one form of my invention that construction and proper use'of the apparatus will effectively demonstate the theory, the use, and the utility of my invention.

It is emphatically stated that all metals used in the construction of the apparatusdescribed in this application must be pure, inactive and absolutely free from any entrapped energy or bound electrical charges.

Obviously many other modifications and variations of the invention as hereinbefore set forth may be made without departing from the spirit and scope thereof, and therefore only such limitations should be imposed as are indicated by the appended claims.

What I claim and desire to secure by Letters Patent of the United States is as follow-s:

1. A method for detecting radiant energy emanatin from subterranean petroleum deposits that comprises surrounding an ionization chambeer with shielding against earthly radiant energy except for a portion of said shielding between the chamber and the earths surface which excepted portion of the surrounding shielding shields the ionization chamber from earthly ionizing radiation, moving said ionization chamber and surrounding shielding to direct said excepted portion of the shielding at any desired angle in relation to the earths surface, charging negatively electrostatically the inner surface of said chamber, subjectin said shielded chamber to the radiant energy emanating from subterranean petroleum deposits, determining electronically the rate of dissipation of the charge on the inner surface of said chamber, comparing that rate of dissipation with the rate of dissipation of a similar negative electrostatic charge on the inner surface of said chamber when shielded against radiant energy emanating from subterranean petroleum deposits, the presence of petroleum deposit emanations encountered from a limited area of the earths substrata being detected thereby.

2. A method for measuring radiant energy for the relative amount of subterranean petroleum deposit emanations encountered in geophysical explorations that comprises surrounding an ionization chamber with shielding against earthly radiant energy except for a portion of said shielding between the chamber and the earths surface which excepted portion of the surrounding shielding shields the ionization chamber from earthly ionizing radiation, moving said ionization chamber and surrounding shielding to direct said excepted portion of the shielding at any desired angle in relation to the earths surface, charging negativey electrostatically the inner surface of said chamber, subjecting said chamber to they ically an electrode in said chamber, subjecting said shielded chamber to the radiant energy emanating from subterranean petroleum deposits, determining electronically the rate of dissipation of the electrode charge, comparing that rate of dissipation with the rate of dissipation of a similar positive electrostatic charge on the electrode when shielded against radiant energy emanating from subterranean petroleum deposits, the presence of petroleum deposit emanations encountered from a limited area of the earths substrata being detected thereby,

4. A method for measuring radiant energy for the relative amount of subterranean petroleum deposit emanations encountered in geophysical explorations that comprises surrounding an ion--' ization chamber with shielding against earthly radiant energy except for a portion of said shielding between the chamber and the earth's surface which excepted portion of the surrounding shielding shields the ionization chamber from earthly ionizing radiation, moving said ionization chamber and surrounding shielding to dl rect said excepted portion of the shielding at any desired angle in relation to the earths surface, charging positively electrostatically an electrode in said chamber, subjecting said shielded chamber to the radiant energy emanating from subterranean petroleum deposits, determining electronically the change of charge on said electrode, comparing that change of charge on the electrode with the change of a similar positive electrostatic charge on the electrode when shielded against radiant energy emanating from subterranean petroleum deposits, the relative amount of the petroleum deposit emanations encountered from a limited area of the earths substrata being measured thereby.

5. Apparatus for detecting radiant energy emanating from subterranean petroleum deposits encountered in geophysical explorations for locating subterranean petroleum deposits, comprising an ionization chamber, shielding surrounding the ionization chamber for shielding said chamber against earthly radiant energy except for a portion of said shielding between the ionization chamber'and theearths surface with the excepted portion of the surrounding shielding substantially impervious to earthly ionizing radiation incident upon said portion, means for movably mounting said ionization chamber and surrounding shielding whereby said excepted portion of the shielding may be directed at any desired angle in relation to the earths surface, and electronic means for measuring the change in the ionization chamber charge during the operation of the apparatus.

6. Apparatus for measuring radiant energy emanating from subterranean petroleum depos its encountered in geophysical explorations for locating subterranean petroleum deposits, comprising an ionization chamber with an electrode m extending therein, shielding surrounding the a ENCES CITED ionization chamber for shielding said chamber The following references are of record in the against earthly radiant energy except for a porfile Of this P tent! tion of said shielding between the ionization 5 UNITED STATES TENT chamber and the earth's surface with the ex- Number Na mm cepted portion of the surrounding shielding subme stantially impervious to earthly ionizing radia- 3 Neufeld 1 5' 1 tion incident 'upon saidportion, means for mova- 3 Piety Apr. 13, 1943 bly mounting said ionization chamber and sur-' 10 OTHER REFERENCES rounding shielding whereby said excepted porl l zyfl v l- 1 36, (2) pp. 149-157. mm of the shielding may be directed at any de Harrington sbientmc American, september sired angle in relation to the earth's surface, and

electronic means for measuring the relative 1935'pp'131 and amount of petroleum deposit emanations err-' countered from a limited area of the earths substrata.

WALTER ARMSTRONG. 

